Multiple epidemic waves in delayed susceptible-infected-recovered models on complex networks
Shaofen Zou1, Jianhong Wu, Yuming Chen
1College of Mathematics and Econometrics, Hunan University, Changsha, Hunan 410082, People's Republic of China. hnsfz2008@gmail.com
Summary
A large time delay in epidemic models can trigger multiple epidemic waves. When transmission rates are high, subsequent waves may exhibit larger peaks than the initial outbreak.
Area of Science:
- Epidemiology
- Network Science
- Mathematical Biology
Background:
- Understanding epidemic dynamics is crucial for public health interventions.
- Complex networks provide realistic structures for disease transmission modeling.
- Time delays can significantly alter disease progression and outbreak patterns.
Purpose of the Study:
- To investigate the impact of time delays on epidemic curves within a susceptible-infected-recovered (SIR) model.
- To analyze how time lags influence the shape and potential for multiple waves in epidemic spread.
- To determine the conditions under which time delays induce complex epidemic behaviors.
Main Methods:
- Utilizing a delayed SIR epidemic model.
- Simulating disease spread on an uncorrelated complex network.
- Analyzing epidemic curves to identify wave characteristics and amplitudes.
Main Results:
- A significant time delay can lead to the emergence of multiple epidemic waves.
- When the transmission rate exceeds a critical threshold, delayed models exhibit pronounced secondary and subsequent waves.
- The amplitude of later epidemic waves can surpass that of the initial wave due to time lags.
Conclusions:
- Time delays are a critical factor in shaping epidemic dynamics on complex networks.
- The presence of multiple, amplified waves suggests potential for prolonged or resurgent outbreaks.
- Findings highlight the importance of incorporating time lags into epidemic modeling for accurate prediction and control.
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